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Farming on the Edge: Getting the Most Out of Marginal Lands

I’m Barbara Klein with the VOA Special English Agriculture Report.

 
 
To call something "marginal" means it is not very good.  Farmers have their own way to define marginal land: It is the last to be planted under good conditions, and the first to be avoided under poor conditions.

Low quality soil is not the only reason land could be considered marginal.  It might be in an area where rainfall is limited.  Or a hillside might rise too steeply. 

There are uses for marginal land, however.  Most often it is used as grassland.  Grasses provide excellent feed for grazing animals like cattle, sheep and goats. 

Grass seed can be bought from a supplier.  Or native grasses can be used.  But it is important to establish good ground cover to avoid soil loss through erosion.

Forage crops like clover and alfalfa can be planted.  These members of the legume family provide high protein food for grazing animals.  They also improve the quality of the soil. 

Most plants use up nitrogen.  But legumes put nitrogen back into the soil.  Forage crops also help limit erosion. 

However, using marginal land for grazing is not a simple issue.  There is a risk of overgrazing.  Cattle can damage forage crops by eating down to the roots.  Also, the weight of the animals crushes the soil and can make it too hard for growing.

A way to reduce the harm is to move animals from one field to another.  This method is known as rotational grazing.  Experts say rotational grazing is extremely important for marginal land. 

Another use for marginal land is for tree crops.  Studies have shown that the white pine and loblolly pine are two kinds of trees that grow well on such land.  They grow fast and provide good quality wood.  Another tree is the poplar, found in many parts of the world.  Slower-growing trees like the black walnut also provide a nut crop.

Trees support the soil.  They reduce the effects of wind and rain.  And they help block the sun. 

Failure to take the care needed to protect marginal lands can make a bad situation worse.  But good planning can turn a marginal resource into a highly productive one. 

This VOA Special English Agriculture Report was written by Mario Ritter.  Our reports are online at voaspecialenglish.com.  If you have a question about agriculture, send it to special@voanews.com.  We might answer it on our program.  I'm Barbara Klein.

Space Shuttle in Orbit but Future Flights Suspended
Written by Caty Weaver, Jeri Watson and Jill Moss

 For updates on the shuttle flight, go to VOA News

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VOICE ONE:

This is SCIENCE IN THE NEWS, in VOA Special English.  I’m Barbara Klein.

VOICE TWO:

And I’m Bob Doughty. On our program this week, we tell about a new panda baby born in Washington, D.C. and one of the world’s greatest athletes.  But first, America’s space shuttle Discovery returns to space.

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VOICE ONE:

 
Astronaut Steve Robinson after a spacewalk on August 1
The American space shuttle returned to the skies on July twenty-sixth.  Discovery and its seven-member crew were launched from the Kennedy Space Center in Florida to fly to the International Space Station.

The launch was supposed to have taken place on July thirteenth.  But, space agency officials called it off just a few hours before the launch because one of Discovery’s fuel tank sensors failed a test.  NASA officials investigated the system for several days but they never learned the cause.  They decided to set up another launch for last Tuesday.  Discovery is now connected to the space station, orbiting hundreds of kilometers above the Earth.

VOICE TWO:

 
This is the first space shuttle flight in two and one-half years. NASA suspended the flights following the deadly explosion of the shuttle Columbia in two thousand three.  All seven crewmembers were killed. A team of investigators found that the explosion was the result of damage done to the shuttle during the launch.

A piece of lightweight protective material fell off of the shuttle’s external fuel container.  The object hit the shuttle at a high rate of speed and made a hole in one of the wings.  This permitted extremely hot gases to enter the shuttle and destroy the spacecraft as it returned to Earth.   

VOICE ONE:

During the launch of Discovery on Tuesday, a large piece of protective material again broke off the external fuel tank. The object apparently did not hit the space shuttle. But program manager William Parsons decided to suspend future shuttle flights until NASA experts fix the problem. He said: “Until we fix this, we’re not ready to fly again.” He said he did not know how long it would take.

After the destruction of Columbia, the investigators advised NASA to carry out fifteen steps to increase safety before flying another shuttle.  One of the major changes involved the fuel tank. NASA engineers thought they had reduced the risk that its protective material would break off during launch.  NASA experts also increased the number of cameras at the launch area.  And they designed a new warning system to inform crewmembers on Discovery and ground control of any problems.

VOICE TWO:

Discovery’s cameras recorded pictures of material flying off the shuttle as it launched last Tuesday.  Investigators inspected the pictures closely.  On Wednesday, Discovery’s crew used a special device to examine all areas of the spacecraft for signs of damage.  They found no serious damage.

Discovery’s commander is retired Air Force Colonel Eileen Collins.  She was the first woman to fly a space shuttle and is the first female shuttle commander.  The Discovery pilot is James Kelly.  Other crewmembers include a rock and roll guitar player, astronauts from Japan and Australia and another female astronaut.

VOICE ONE:

Discovery will be in space for thirteen days.  Its crew is very busy.  They transported supplies and equipment to the space station.  And, astronauts Steve Robinson and Soichi Noguchi are performing space walks outside the space shuttle.  They are testing possible new ways to make repairs to the orbiting space station.  On the final space walk they are to remove and replace a broken piece of equipment on the outside of the station.  The also will place a television camera and light system on the outside of the station.

NASA has said this flight is a test of new safety measures on the space shuttle.  But now it is not known if the next shuttle, Atlantis, will be able to fly in September. You can learn more about America’s return to space at NASA’s Web site.  The address is www.nasa.gov.

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VOICE TWO:

 
Mother and cub on July 26
The giant pandas in Washington, D.C., recently produced the first panda baby born at the National Zoo in sixteen years.  Male panda Tian Tian (tee-YEN tee-YEN) and his mate Mei Xiang (may-SHONG) became parents July ninth.  Panda cubs born in earlier years to the zoo’s first pandas survived only a few days. 

The birth of the new baby was the result of artificial insemination.  Reproductive material from Tian Tian was placed in Mei Xiang’s body March eleventh.  The process was completed during the two or three days a female panda can become pregnant each year.  This short fertile period is one reason why giant pandas are in danger of disappearing from Earth. 

VOICE ONE:

At birth, the new cub appeared healthy. It was extremely small.  It weighed only about one hundred grams. Experts at the zoo have praised Mei Xiang’s skills as a mother.  They say the cub is gaining weight from its mother’s milk.  It is active and is making noise.

The cub was pink in color and had no hair at birth.  But the skin around its eyes is getting darker now.  The animal’s back legs and ears also are darkening.  These places will develop into black fur.  The rest of its body will have mainly white fur.  These markings give giant pandas their special appearance. 

Baby pandas sometimes do not survive in zoos. So Mei Xiang and the cub are being kept by themselves to prevent infection.  Zoo workers watch them through cameras that are connected to the Internet so people around the world can watch them, too.  

VOICE TWO:

The cub will be sent to China at age two.  China loaned the two adult giant pandas to the National Zoo for ten years.  They arrived five years ago.  China has also loaned pandas to three other American zoos.  China receives a great deal of money in return.  The money helps support programs to save giant pandas in the wild.  Experts hope that the giant pandas at other zoos in the United States will also produce babies this year. 

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VOICE ONE:

 
 
On July twenty-fourth, Lance Armstrong of the United States won the Tour de France bicycle competition for the seventh straight year.  His victory sets a new world record.  Armstrong said he will not race again next year. The three-week competition is considered the most difficult cycling race in the world. Racers must ride almost three thousand six hundred kilometers. 

They must ride uphill through the Alps and Pyrenees Mountains. And they must race at high speeds over flat land.  Winning requires great athletic ability. 

VOICE TWO:

Lance Armstrong is thirty-three years old. He is one of the best athletes in the world. Scientists say his body operates better than the average person. For example, his heart can beat more than two hundred times a minute. It pumps an extremely large amount of blood and oxygen to his legs.  Scientists say only about one hundred other people in the world have this ability.

A scientist at the University of Texas at Austin studied the cyclist from the age of twenty-one to twenty-eight while Armstrong was in training.  The Journal of Applied Physiology published his study in June.

VOICE ONE:

Edward Coyle is the head of the Human Performance Laboratory at the University of Texas in Austin.  He tested Armstrong five times from nineteen ninety-two until nineteen ninety-nine.  Each time, the cyclist rode a fixed bike for twenty-five minutes with the work rate increasing every five minutes.

Scientists measured Armstrong’s performance against the amount of oxygen he breathed.  Doctor Coyle discovered an eight percent increase in Armstrong’s muscle power.  Doctor Coyle suspects Armstrong may have developed more of a certain kind of muscle during his seven years of training.  

Doctor Coyle also discovered that Armstrong was able to reduce his body weight and body fat before his Tour de France victories.  This enabled him to increase his power in relation to his body weight by eighteen percent. Doctor Coyle says the results of the study show that long-term training has more of an effect on athletes than scientists thought.

VOICE TWO:

Lance Armstrong is special in another way.  In nineteen ninety-six, when he was twenty-five, he discovered he had cancer of the testicles.  The cancer had spread to his lungs and brain.  Armstrong received chemotherapy treatment and several operations on his brain. After he recovered from the treatment, he began training again in nineteen ninety-eight. The next year he won his first Tour de France race.  Many people believe he is a hero to other people who have survived and are living with cancer. 

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VOICE ONE:

This program was written by Caty Weaver, Jerilyn Watson, and Jill Moss. Cynthia Kirk was our producer. I’m Barbara Klein. 

VOICE TWO:

And I’m Bob Doughty. Join us again next week for Science in the News in VOA Special English. .

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